Yudan Taiteki wrote:That's one definition of "idiom" but the term I used was "idiomatic", which means "peculiar to or characteristic of a particular language or dialect." In linguistics the term is used just to mean "a language the way native speakers use it" and I guess that's how I was using it too.

...which is, by the way, a perfectly valid use for the term. Whether a given phrase is "an idiom" or not is rather aside from the point anyway.

monkeykoder wrote:This may just be me but what I see is taking English idioms and trying to translate them into Japanese and saying you're getting "non-idioms". Specifically from my understanding of the word "idiom" we're talking about something peculiar to that language's normal way of doing things. So if "つける" is usually used for "turn on" then it isn't an idiom. I'm not saying I'm 100% correct this is just my interpretation of the word. All I'm trying to say is unless it breaks the Japanese rules for language it doesn't fit the classification of "idiom" by my understanding of the word.

When classifying things in a language then yes, "an idiom" is a phrase that is generally understood amongst native speakers to have meaning that is more (or different) than the sum of its parts.

However "unidiomatic" does not mean "not an idiom". In this case "unidiomatic" means that the sum of the parts does not add up to what you intend to say. It does not follow the way a native speaker would express something. It's something that would sound wrong, or make no sense at all to a native speaker.

You might learn that "つける" can mean "turn on" and use it correctly in this case, but that would be a lucky case. This works with very generic verbs. See if you can correctly say "answer the phone" if all you know is "answer" and "phone".

The examples I gave are just examples of what you might come up with if you don't learn the correct way to say things. A lot of the time if you just put words together without following a native speaker's example, you will produce something that a native would never say.

That's why you need to expose yourself to words used with examples and extra context as much as you can.